The 7mm STW, or 7mm Shooting Times Westerner was originally a wildcat designed in 1989 by Layne Simpson, a gun writer for Shooting Times magazine. The design includes a slight decrease in body taper, compared to the original 8mm Remington Magnum case. Throat design was also changed to include a straight section. This improves accuracy potential. The 7mm STW was adopted as a SAAMI cartridge about 1996. The 7mm STW has impressive velocity potential and can deliver good ballistics with a variety of bullets and powders. 

This text is based on information from “Cartridges of the World”, Hodgdon reloading manual, the cartridge designer and/or own resources.